solve X+√y=21
y+√x=29

Question

solve     X+√y=21
              y+√x=29

anonymous · Answer

try and make y = x +something
then swap y for that x+ something
example
y + x = 4
2y + x = 10
so get y alone for one of them.
y = 4-x
now on the second equation swap y for 4-x
2(4-x) +x = 10
8-2x + x = 10
-2x = 2
x = -1! now that we have x just plug in and solve for y
y = 4-x
y = 4 - (-1)
y = 5!

anonymous · Answer

$$x + \sqrt{y}=21$$ so this tells us that 
$$x=21-\sqrt{y}$$

anonymous · Answer

I guess y=25 and  x=16 but I want a real solution

anonymous · Answer

√y=21-x
√x=29-y
square both term and solve for x and y.

anonymous · Answer

y=441-42x+x^2
x=841-58x+y^2
 what can I do with them?

anonymous · Answer

if what you did is correct, then everywhere you see y on the second equation plug in what you got for y. 
y = 441-42x +x^2 right? 
soooooo
x=841-58x+(441-42x+x^2)^2
this is to say y ----^ but you now have a y=something

anonymous · Answer

and now you can solve for x! once you have x, you can plug that in and solve for y

anonymous · Answer

i double checked your math and you are on the right track!

anonymous · Answer

the last EQUATION
$$x=841-58(21-x)^{2}+(21-x)^{4}$$